"Christian Kaiser" wrote:

...does a Poly-Isocyanurate persist two decades of the temperatures
that the collectors have? The max temperature of that insulation
material is about 300 deg F (150 deg C) - pretty near to the stagnation
temperature, or even below it for good collectors.

When Gary sent me the nice solar pond water heater model he tested in
Montana, I put it together in partial sun with the pump unpowered and
had a meltdown :-) The 2" Styrofoam cover (under a layer of EPDM under
2 layers of polycarbonate) developed multiple 1" hills and 2" valleys.

A 2" double-foil polyiso replacement with foil-taped edges has worked
fine so far. One polyiso ap engineer says it's good to at least 350 F,
when the surface starts to develop cosmetic wrinkles. But I think we
should replace both polycarbonate layers with greenhouse polyethylene
to lower the cost and assembly complexity and stagnation temperature.

I put some polyiso on top of a toaster oven, and it deformed badly...

Nick

Don't miss this opportunity to have every solar question you ever asked
answered in three different ways...

Join PE Drew Gillett and PhD Rich Komp and me for a workshop on Solar House
Heating and Natural Cooling Strategies at the first Pennsylvania Renewable
Energy Festival at 9 AM on Saturday September 24, 2005 near Allentown. See

http://www.paenergyfest.com/workshop-info.shtml

wrote:
"Christian Kaiser" wrote:


...does a Poly-Isocyanurate persist two decades of the temperatures
that the collectors have? The max temperature of that insulation
material is about 300 deg F (150 deg C) - pretty near to the stagnation
temperature, or even below it for good collectors.


When Gary sent me the nice solar pond water heater model he tested in
Montana, I put it together in partial sun with the pump unpowered and
had a meltdown :-) The 2" Styrofoam cover (under a layer of EPDM under
2 layers of polycarbonate) developed multiple 1" hills and 2" valleys.

Here are some additional (unintended) thermal sculptures.
http://www.builditsolar.com/Experimental/pinkfoam.htm



A 2" double-foil polyiso replacement with foil-taped edges has worked
fine so far. One polyiso ap engineer says it's good to at least 350 F,
when the surface starts to develop cosmetic wrinkles. But I think we
should replace both polycarbonate layers with greenhouse polyethylene
to lower the cost and assembly complexity and stagnation temperature.

I like polycarbonate on the outside layer for weathering, durability,
impact resistance, AND the dog can't chew a hole through it to get to
a warm spot (like she did on my poly film sunspace) :-)



I put some polyiso on top of a toaster oven, and it deformed badly...

Nick

Don't miss this opportunity to have every solar question you ever asked
answered in three different ways...

Join PE Drew Gillett and PhD Rich Komp and me for a workshop on Solar House
Heating and Natural Cooling Strategies at the first Pennsylvania Renewable
Energy Festival at 9 AM on Saturday September 24, 2005 near Allentown. See

http://www.paenergyfest.com/workshop-info.shtml



--


Gary

www.BuildItSolar.com

"Build It Yourself" Solar Projects









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Gary wrote:

I like polycarbonate on the outside layer for weathering, durability,
impact resistance, AND the dog can't chew a hole through it to get to
a warm spot (like she did on my poly film sunspace) :-)

That's OK too. Does your dog get to vote?

Nick